Solving sow lameness starts with prevention

Lameness issues continue to be a significant problem in sow herds, causing 40% to 50% of all sow removals, according to Bill Minton, DVM, Four Star Veterinary Service in Chickasaw, Ohio.

“What hurts most is when the culling for lameness occurs at 3rd parity,” Minton said. “It takes almost to the 3rd parity to break even on the cost of raising, acclimating and getting that animal into production. We are removing animals we haven’t even paid for. This has become a significant cost that is often overlooked.”

Minton advocates taking steps to reduce lameness problems early and to increase sow longevity up to 7 parities in herds. Not only will this lower costs in a system, it will improve worker well-being by not having to deal with the problems associated with lame sows.

Pay attention to gilt selection

Many lameness problems can be prevented by selecting gilts ahead of time, he explained. Producers should try to evaluate incoming gilts as soon as possible before entering the herd. This can be done in the grow-development units or during the quarantine period. Ensure gilts are structurally sound and the right age and weight before bringing them into a sow unit.

He recommended taking a good look at how gilts move and walk in a pen. Make sure the animals have good body confirmation, good hoof quality, and stand well on their feet. They should not be stiff gaited or have long toes.

The best size and weight for gilts entering a sow unit is around 300 lbs. and 28-30 weeks of age, he added. If gilts must be brought into a herd earlier, consider skipping a heat cycle to help the gilt develop adequate body condition.

“Put an emphasis on bringing in the right quality animals,” he said. “Spend some time selecting gilts. We easily overlook this and assume everything is okay. Then we bring in animals [to meet breeding targets] and it backfires in the long run.”

Watch every sow every day

Better observation of sows in gestation is key to reducing lameness issues that lead to culling, Minton emphasized.

“In gestation, make sure you get up every sow and observe every one for signs of early lameness,” he said. “Observe sows especially at feeding time to see if they are shifting weight, tapping a foot, or not bearing equal weight on all four legs. Do they have any swelling, cuts or bleeding? Observe sows while walking through the gestation barn or farrowing rooms.

“If we know what we are looking for early enough, we do have the opportunity to treat lameness,” he explained. “Oftentimes we intervene too late and don’t get a response out of our treatment.”

Treatment options

If the decision is made to treat an animal, Minton said there are several options depending on the cause of lameness. For health-related problems, products such as systemic antibiotics, pain relievers and anti-inflammatory products may help if problems are caught early enough.

Because nutritional deficiencies can also lead to lameness, review sow rations to determine if there are nutritional concerns. The addition of some trace minerals like biotin and zinc may help improve hoof strength, Minton added.

Providing individual sow care is another option. “Even special attention and TLC for some animals will help,” he said. “Remove them from a pen and put them in a hospital stall with a rubber mat for better footing.”

Hoof trimming can solve some lameness issues. “It helps especially for those long dew claws or an outside toe that’s quite a bit longer than the inside toe,” he explained. “We can use lopping shears and trim that off. A lot of times that will correct the confirmation of the animal so she is more comfortable walking.”

Another suggestion is using copper-sulfate foot baths. Minton said copper sulfate is an antiseptic for the hoof, which can help improve hoof strength. He suggested providing the foot baths for gilts when entering the sow barn and sows to walk through when moving between farrowing and gestation units.

Maintain good housing, environment, handling

Many other factors cause lameness in sows and gilts. These range from different types of housing, flooring, air quality and temperature to poor handling and fighting among animals.

Producers need to maintain a good environment and housing with proper animal handling procedures to minimize lameness issues. Overcrowding, improper ventilation rates, mycoplasma or erysipelas, and the health status of incoming gilts are a few factors that can lead to lameness.

Minton suggested using treatment-card data and other records to identify trends and specific issues that may be causing problems within a unit. It will offer guidance on areas that could be addressed.

“I think a lot of lameness is preventable and some of it is treatable,” he added. “But ultimately, it has a negative impact on sow culling and mortality. Intervention will have a positive impact on the sow herd.”

Early identification critical in preventing sow lameness

Sow lameness continues to trouble hog operations in the US, causing high numbers of involuntary removals from herds. These expensive sow removals can be reduced by identifying lameness issues early and addressing equipment hazards that lead to sow injuries, reported Michael Pierdon, VMD, Four Star Veterinary Service, Elizabethtown, Pennsylvania.

“When a sow develops lameness that is severe enough that she is no longer able to get to the feeder…she will need to be removed regardless of her age or production history or stage of gestation,” Pierdon added. “Those involuntary removals are really damaging financially to sow herds.”

Identify gait issues early

Injury to the hoof and foot cause most lameness that eventually leads to removals. Pierdon said these injuries can go unnoticed by farm staff because pigs are good at hiding them.

“Those injuries can become infected, and the infection festers and becomes more severe over time, eventually causing significant damage within the joint, bones or foot,” he said.

“Once the damage progresses to that point, the animals aren’t recoverable. Medically we’re just not able to manage them back to health.”

The key to preventing this scenario is training farm workers to identify animals much earlier in the course of the disease.

“We need to identify animals when they have a gait abnormality or are not walking smoothly,” Pierdon explained.

“Aggressive antibiotic treatment strategies can have some success in resolving these issues before they develop into a [high] level of severity.”

If farm workers wait to treat an animal until it is unwilling to put weight on a leg, it is too late. Clinically resolving lameness at this point is very unlikely.

Pen-gestation hazards

“Lameness has really risen in importance as we’ve begun to house sows more often in group-housing situations,” Pierdon added. “An animal needs to be able to move and move effectively without pain to compete and thrive in a group environment.”

The move to group housing offers more opportunities for sows to move around, interact with other sows and become injured, which begins the lameness process, he explained.

In addition, many sow barns are equipped with slatted flooring designed for stall gestation. When converted to pens, the slats are too wide for sows to walk on, and injuries occur when feet get stuck in the slat gaps.

Pierdon said he also has seen injuries due to hardware issues, like sharp edges sticking out of the floor or feeders facing the wrong direction.

In barns where the facility issues were fixed, the number of lameness issues improved, he added.

Genetic improvements

Compounding the lameness issue are sow genetics that haven’t focused on traits needed for pen gestation.

“Animals with heavier bones, with bigger feet, will likely do better as far as lameness goes,” he said. “We really need help from our genetic partners on that, on selecting for traits that ensure soundness and survivability in these housing systems.”

While lameness will never be fully solved, Pierdon believes the industry will learn to manage it better.

“The biggest drivers will be facility design and genetic improvement, refocusing on structure and durability on the genetic side,” he said. “But also continuing to experiment and study facility design to find options that reduce the risk of injury to the animals.”

In the meantime, attention to the first signs of lameness will help farms better handle sow injuries and lower involuntary removals from the herd.

 

 

Strategies to curtail rising sow-lameness problems

Sow-lameness issues are on the rise, especially for sows in group housing, according to Michael Pierdon, VMD, Four Star Veterinary Service. Lameness is a leading reason that sows are culled early from the herd.

“Sow lameness is not a new problem, but it has come into focus as sows are moved into pen gestation,” Pierdon explained. “Structural soundness is much more important in a loose-housing environment than in a stall environment. They really need to be sound in order to survive in the herd.”

He sees other causes of sow lameness, too, including inadequate gilt nutrition, pen hazards leading to injuries and delayed identification of lameness.

Located in Elizabethtown, Pennsylvania, Pierdon works with many hog producers who house gestating sows in pens. He employs four management strategies to address sow lameness and reduce the number of involuntary removals from herds.

1. Structural soundness

Preventing lameness starts with gilt selection. “Make sure you get animals with structural soundness and integrity because poor structure will lead to lameness quickly,” he said.

Unfortunately, genetics companies have not been forced to focus on leg and foot soundness since sows moved into gestation stalls 30 years ago. Pierdon hopes that changes, and there’s a renewed focus on sows with bigger feet and bone structure to handle the rigors of pens.

“Once you establish proper structure and good gilt selection, then you must develop the gilt properly to ensure she meets her genetic potential, and that’s largely done through nutrition,” he continued. “She must have the nutritional program that supports bone and hoof health, or we predispose her to lameness issues.”

2. Reduce injuries

Injury is a leading cause of sow lameness, Pierdon said. Most of the injuries are to the foot and hoof.

“We are learning that a significant amount of lameness is due to ascending infections from damage to feet and breaks in the hoof wall that get infected,” he said. “If that infection isn’t identified early, it has the chance to spread deeper into the tissue and joints and ultimately becomes an unresolvable issue.”

Poor equipment design increases the chance of sow injury.

“Sow barns built for gestation stalls typically have a pretty wide slat gap,” Pierdon said. “But when the sows must move around on those floors when the barns convert to group housing, the gap is wide enough that a sow can get her toes stuck and damage her hoof. We need to continue to work toward smaller gaps or another type of flooring.

“We also see a lot of gating and feeders that are fastened to the floor with bolts sticking up and sharp edges all in the path of feet. Anything that can be stepped on and cause foot injuries are what we really worry about,” he added.

3. Identify lameness early

One key to reducing lameness is detecting it early before the problem progresses to the point it can’t be resolved. This can be difficult.

“Sows are tough and will hide or manage to survive with their lameness for quite some time until it becomes really severe,” Pierdon said. “If you gauge lameness by the sows not eating that day, then it is too late. By the time they can’t get to the feeder, their lameness is so advanced that the likelihood of resolving it is minimal.”

He recommends evaluating sows daily to watch their gaits and look for any sign of lameness like unsteadiness, shifting weight or gingerly tapping feet on the floor. Waiting for sows to progress to three-leg lameness is too late to identify the problem and expect recovery.

“Workers have to be very attentive to the animals,” he explained. “They have to really watch sows stand and move in order to identify lameness.”

4. Proactive treatment

“Workers also have to err of the side of aggressive treatment,” he continued. “They need to be proactive if they want a chance to resolve these issues.

“A lot of people do not realize how severe the damage is by the time they identify it and start treating these animals. Workers get frustrated because they try to treat lame animals and it doesn’t work. Sows must be identified and treated way earlier in the course of the lameness issue.”

Treatment options depend on the severity and type of lameness. Pierdon recommends working with a veterinarian to determine the best treatment protocols.

“Lowering sow lameness often has to be a multifaceted approach,” he added. “It’s a real challenging issue when sows are housed in pens.

“Success to me is keeping lameness at a manageable level and maintaining normal removal rates. It also is giving the crew wins where they feel like they have some power to influence this issue and reduce the number of animals they identify as lame.”

 

Check with your Four Star veterinarian to investigate sow lameness at your farm.